IPN without active merchant

ipn_example.rb

#from http://www.ruby-forum.com/topic/163331#817338
#this code will also work if you are not using active merchant.
 if request.post?
  #new
  @params = params
  @params[:cmd] = "_notify-validate"
  @params.delete(:action)
  @params.delete(:controller)

  url = URI.parse("https://www.paypal.com/cgi-bin/webscr")
  req = Net::HTTP::Post.new(url.path)
  req.set_form_data(@params)
  sock = Net::HTTP.new(url.host, url.port)
  sock.use_ssl = true
  response = sock.start {|http| http.request(req)}

  item_name = params[:item_name]
  payment_status = params[:payment_status]
  payment_amount = params[:mc_gross]
  payment_currency = params[:mc_currency]
  payer_email = params[:payer_email]
  receiver_email = params[:receiver_email]
  txn_id = params[:txn_id]

  if response
    @user = User.find_by_email(payer_email)

    if @user
      #find account and update
      @account = Account.find_by_user_id(@user.id)
      unless @account
        @account = Account.new()
      end
      @account.status = 'Init'
    end

    if response.body == 'VERIFIED'
        if payment_status == 'Completed'
          @date = Date.today() + 365
          @account.ipn = 'Completed'
          @account.status = 'Completed'
          @account.amount = payment_amount
          @account.paypal_id = txn_id
          @account.expires = @date
          @account.save
          @user.status = "Open"
          @user.expires = @date
          @user.save(false)
        else
          @account.status = 'Not Verified'
          @account.save
          @account.update_attribute(:ipn,'Pending')
        end
    else
        @account.status = 'Not-Passed'
        @account.save
    end

  end
end

render :nothing => true